package com.ms.utils;

import cn.hutool.core.lang.UUID;
import org.springframework.core.io.ClassPathResource;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;

import java.util.Collections;
import java.util.concurrent.TimeUnit;

public class SimpleRedisLockImpl implements IRedisLock{

    private StringRedisTemplate stringRedisTemplate;

    private String name;

    private static final String KEY_PREFIX = "lock:";

    private static final String ID_PREFIX = UUID.randomUUID().toString(true).toString();

    private static final DefaultRedisScript<Long> UNLOCK_SCRIPT;

    static {
        UNLOCK_SCRIPT=new DefaultRedisScript<>();
        UNLOCK_SCRIPT.setLocation(new ClassPathResource("unLocks.lua"));
        UNLOCK_SCRIPT.setResultType(Long.class);
    }
    public SimpleRedisLockImpl(String name,StringRedisTemplate stringRedisTemplate){
        this.name=name;
        this.stringRedisTemplate=stringRedisTemplate;
    }

    /**
     * 获取锁
     * @param timeoutSec
     * @return
     */
    @Override
    public boolean tryLock(long timeoutSec) {
//        获取线程id
         String threadId = ID_PREFIX + Thread.currentThread().getId();
//         获取锁
        Boolean success = stringRedisTemplate.opsForValue().setIfAbsent(KEY_PREFIX+name,threadId+"",timeoutSec, TimeUnit.SECONDS);
        return Boolean.TRUE.equals(success);
    }

    /**
     * 释放锁
     */
    @Override
    public void unlock() {
////        获取线程标识
//        String threadId = ID_PREFIX + Thread.currentThread().getId();
////        获取锁中的标识
//        String id = stringRedisTemplate.opsForValue().get(KEY_PREFIX+name);
////        判断是否一致
//        if(threadId.equals(id)){
////            释放锁
//            stringRedisTemplate.delete(KEY_PREFIX+name);
//        }
        stringRedisTemplate.execute(UNLOCK_SCRIPT, Collections.singletonList(KEY_PREFIX+name),ID_PREFIX+ Thread.currentThread().getId());
    }
}
